Pneumatic weft inserting means



March 10, 1964 TE STRAKE 3,124,167

PNEUMATIC WEFT INSERTING MEANS Filed Dec. 28, 1959 Li: I 5%: :1

United States Patent Ofiice 3,124,167 Patented Mar. 10, 1964 3,124,167 PNEUMATEC WEFT ENSERTHNG MEANS Larnhertus te trake, Huize Gelria, Deurne (Nliru), Netherlands Filed Dec. 23, 1959, Ser. No. 862,147 Claims priority, appiication Netherlands Jan. 19, 1959 Claims. (Cl. 139-127) The invention relates to a device for transporting one or more threads by means of air. The invention also relates to a weaving loom provided with such a device, for blowing the weft-thread into the shed.

In order to step up the production of weaving looms attempts have been made to blow the weft-thread into the shed by means of an air-jet. Diificulties arise since the air flowing out of such a blowing device becomes very turbulent because of friction with the surrounding atmosphere, so that the thread can be blown only over a very short distance with a moderate directioning effect.

in practice usually fabric webs of only fifty centimeters or less can be woven if it is not desired to use reciprocating blowing and suction nozzles. A nozzle, reciprocable in the shed, has to be made relatively heavy, since the course is rather long. Because of the long course one is compelled to apply high speeds to the reciprocable nozzles, therefore encountering the mass inertia difficulties experienced with the conventional type of Weaving looms.

The present invention provides for the conveyance of a thread by means of air over an unlimited distance. This is attained according to the invention by a plurality of spaced blowing devices operating in the direction of transport, each being provided with a catching device for the thread in order to bring the arriving thread from a preceding blowing device into the path of the air discharged from the nozzle of a succeeding blowing device. The catching device for the thread preferably utilizes air suction. One embodiment of the device for transporting one or more threads comprises an injector tube secured to a jet nipple. The jet nipple is connected to a pressure line. The injector tube is provided with an opening, positioned behind the tip of the jet nozzle, which acts as a suction opening. According to the injector-principle, secondary air is drawn in through this opening and this suction action acts as a catching device for a thread blown within the range of said suction action. Such an embodiment is described in U.S. Patent No. 2,925,833, issued February 23, 1960. The suction opening or aperture advantageously merges into a slit which extends in the longitudinal direction of the injector tube.

Consequently with a plurality of such devices it is possible to transport a thread over very long distances, e.g. tens of meters, when a series of booster blowing stations is formed. Based on this invention therefore a Weftthread can be blown into the shed over the full width of the cloth irrespective of the number of warp threads,

without proceeding to laterally insert a reciprocating blowing nozzle in the opening of the shed from the side.

A weaving loom according to the invention is characterized in that in the direction of the weft over the width of the cloth, or over the width of the path of the warpthreads, a series of blowing devices are provided which may be periodically inserted in the shed of the warpthreads.

According to the invention an embodiment is illustrated herein in which the blowing devices are arranged above or below the path of the warp-threads and, when the shed is opened, can be inserted into the shed through the lower or upper lease between the warp-threads. The blowing devices are advantageously mounted on bellcranl; levers which can be so controlled that these levers send the blowing devices into and out of the shed in order to allow the reed to pass during the beat-up stroke and to allow the shafts to change the shed.

in the drawings:

FIG. 1 is a diagrammatic side view of a thread-conveying device according to the invention;

FIG. 2 is a diagrammatic plan View of FIG. 1;

FIG. 3 is a front view of a reed of a weaving loom, provided with a thread-conveying device according to the invention; and

FIG. 4 is a front view of a part of the reed, a blowing nozzle being mounted on a bell-crank lever.

The invention comprises a series of blowing devices A, B and C. Each device consists of an air nozzle 1 and an injector tube 2. The nozzles blow air from the device A to the device B and from device B to the device C. The air jets therefore are practically aligned. A thread 3 is blown through the device A to the device B and hence to the device C and further.

The injector tube of the blowing device possesses a suction opening 4 near the jet nozzle 1 for drawing in a thread by means of the secondary air, which is drawn into the injector tube by the primary air discharging from the jet nozzle, as explained hereinbefore.

The initial position of the thread is shown in FIG. 1 by a dotted line between the blowing devices A and B. However, it is not necessary to so accurately align the nozzle A that the beginning of the thread 3 arrives just before the opening 3. The thread 3 need only arrive in the proximity of the opening or can even pass the opening 4, as shown by a dash-d0t line between the blowing devices B and C.

If the thread 3 should pass the opening 4, the thread would be drawn by the suction action and take the normal course when further blowing the thread, as shown with a full line. The speed of conveyance of the thread can be materially increased if the opening 4 merges into a slit 5 in the wall of the injector tube 2. In either case the blowing devices A, B and C can be removed from the shed after their conveying action while leaving the thread 3 in the shed. That is, if the thread 3 enters opening 4 and proceeds through injector tube 2, when the blowing device is removed from the shed the thread 3 slips out of tube 2 through slit 5. If the thread 3 does not enter opening 4 it is still conveyed forwardly through the shed by the cushioning action of the air blowing from nozzle 1 and out through tube 2 as shown over blowing devices B and C and described in the preceding paragraph.

Such a conveying device can readily be applied to a loom, as will be described with reference to FIG. 3. In this figure 6 represents the reed and 7 and 7a represent blowing nozzles. Adjacent to the reed 6 are blowing nozzles 55 connected by means of hell crank levers 9, so as to form a conveying device, as shown in FIGS. 1 and 2.

The bell crank levers 9 together with the nozzles 8 can be brought pivoted out of the path of the reed 6. The nozzles serve for transporting a thread supplied to the nozzle '7. Adjacent the reed 6 are also nozzles 10 together with their bellcrank levers 11, which can be pivoted into the path of th reed, if the thread is being supplied through the nozzle 7a. If the thread arrives from the nozzle 7a, the nozzles 8 are removed from the path of the reed.

Though it is preferred to mount the blowing devices 8 at the lower beam 12 of the reed 6, because this beam is already present below the path of warp threads, the nozzles 8 can also be mounted on a separate support independent of the reed with the same effect.

As shown in FIG. 4 a housing 13 is fixed to the lower beam 12, in which an opening 14 is provided communicating with a pressure line 15.

In the housing 13 a hollow shaft 16 is pivotably supported. The bell-crank lever 9 in the shape of a tube is connected to shaft 16. The tube or bell-crank lever 9 terminates in the air nozzle 1 to which the injector tube 2 is connected. Of course, it is also possible to apply a separate bell-crank lever and a separate air-line.

The tube 9 terminates in the hollow space of the shaft 16 which is connected by an opening 17 to the opening 14 when the blowing device occupies the active position shown in full lines in FIG. 4.

By means of a cam 18 the blowing device can be moved out of the path of the warp threads, e.g. into a non-active position shown by the dotted line. Instead of a cam 18, of course, also a tooth rack or other actuating device can be used in order to bring the blowing device out of the shed at the correct moment. The lower warp-threads 19 and the upper warp threads 20 of the shed are shown.

With a reciprocating movement of the blowing device it passes between the lower warp threads 19.

It is evident that the blowing device can be used above as well as below the warp threads. If they are applied above the path of the warp threads, they will enter the shed between the warp threads 2t).

When the weft thread is blown into the shed, it is held at the end of the shed by means of a suction device. To this end a stay 21 or" the reed is advantageously made as a tube and connected to a suction device. By providing a suction slit 2?; in the wall of the tube, the thread is automatically caught, and the projecting end can be severed by means of a knife, e.g. during the beat-up stroke of the reed.

There has thus been described means by which a thread can be blown over a very wide shed and the width of the cloth to be woven does not now depend on the transport length which was limited with conventional looms. For a normal cloth width of 1 or 1.50 meters the application of one or two blowing devices in the shed sufiices.

I claim as my invention:

1. Weft inserting apparatus for a weaving loom comprising means for introducing a weft thread into an open shed by jet action of air under pressure; at least one Weft conveying nozzle adapted to be inserted by bell-crank lever means into said open shed between warp threads intermediate the warp width of said shed; said weft conveying nozzle being adapted to receive and convey further through said opening shed a thread from said weft introducing means.

2. Weft inserting apparatus for a weaving loom comprising means for introducing a weft thread into an open shed by jet action of air under pressure; at least one weft conveying nozzle adapted to be inserted by an air pres sure tube formed as a bell-crank lever into said open shed between warp threads intermediate the warp width of said shed; said weft conveying nozzle being adapted to receive and convey further through said open shed a thread from said weft introducing means,

3. Weft inserting apparatus for a weaving loom comprising means for introducing a weft thread into an open shed by jet action of air under pressure; at least one weft conveying nozzle adapted to be inserted into said open shed between warp threads intermediate the Warp width of said shed; said Weft conveying nozzle being adapted to receive and convey further through said open shed a thread from said weft introducing means; said weft conveying nozzle comprising a jet nipple secured to an injector tube; said injector tube having a suction aperture, formed behind said jet nipple, which merges with a slit extending in the longitudinal direction of the injector tube.

4. Weft inserting apparatus for a weaving loom comprising means for introducing a weft thread into an open shed by jet action of air under pressure; at least one weft conveying nozzle having a single central blowing hole and positioned intermediate the warp width of said loom; means operative when said shed is opened to insert said weft conveying nozzle into said shed through warp threads forming said shed; said weft conveying nozzle being positioned centrally relative to the path of said weft thread; said weft conveying nozzle being operative when within said open shed to convey said thread by a stream of air from said Weft introducing means further across said warp width in a thread path encompassed on two sides only by the warp threads.

5. Weft inserting apparatus for a weaving loom comprising means for introducing a weft thread into an open shed by jet action of air under pressure; at least one weft conveying nozzle adapted to be inserted into said open shed between warp threads intermediate the warp width of said shed; said weft conveying nozzle comprising a jet nipple and an injector tube extending beyond the tip of said jet nipple; said injector tube having an opening for secondary air to be entrained by a high speed jet emerging from the jet nipple, an open end from which the jet may emerge, and a slit formed in said tube connecting said open end and said secondary air opening; said nipple directing a stream of air substantially parallel to the direction of travel of said weft thread; said weft conveying nozzle being adapted to convey further through said open shed by said parallel stream of air a thread from said weft introducing means and to be removed from said shed after conveying leaving said thread in said shed.

References Cited in the file of this patent UNITED STATES PATENTS 1,721,940 Ballou July 23, 1929 2,854,059 Palmer Sept. 30, 1959 FOREIGN PATENTS 1,196,635 France May 25, 1959 860,970 Great Britain Feb. 15, 1961 583,830 Italy Oct. 18, 1950 

1. WEFT INSERTING APPARATUS FOR A WEAVING LOOM COMPRISING MEANS FOR INTRODUCING A WEFT THREAD INTO AN OPEN SHED BY JET ACTION OF AIR UNDER PRESSURE; AT LEAST ONE WEFT CONVEYING NOZZLE ADAPTED TO BE INSERTED BY BELL-CRANK LEVER MEANS INTO SAID OPEN SHED BETWEEN WARP THREADS 